JP2009243510A - Fluid-filled type engine mount for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid-filled type engine mount for an automobile capable of improving vehicle ride comfort by providing vibration isolation characteristics effective even for the vibration of a large amplitude generated at a lower frequency than that of idling base vibration in addition to the idling base vibration of a high frequency small amplitude in an idling state. <P>SOLUTION: This engine mount has a middle frequency orifice passage 86 tuned to a higher frequency zone than a shaking orifice passage 78 and a lower frequency zone than an idling orifice passage 84, is provided with flow rate regulating members 36, 38, 54, 56, 58, 60 so as to cover both openings 54, 56, 58 at a pressure receiving chamber 68 side of the idling and the middle frequency orifice passages 84, 86, and provided with a bulkhead elastic film 62 so as to cover an opening 46 at a balance chamber 70 side of the idling orifice passage 84. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine mount for supporting an automobile power unit on a vehicle body in an anti-vibration manner, and more particularly to an automobile fluid-filled engine mount capable of exhibiting an anti-vibration effect based on a fluid action of a fluid enclosed therein. It is.

  2. Description of the Related Art Conventionally, a fluid-filled engine mount is known as a kind of automobile engine mount that is interposed between an automobile power unit and a vehicle body and supports the power unit against vibration against the vehicle body. In this fluid-filled engine mount, the first mounting member and the second mounting member that are attached to each of the power unit and the vehicle body are connected by the main rubber elastic body, and a part of the wall portion is main rubber elastic. A pressure receiving chamber constituted by a body and an equilibrium chamber in which a part of the wall portion is constituted by a flexible film are formed, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber. The pressure receiving chamber and the equilibrium chamber are communicated with each other through the orifice passage, and an anti-vibration effect that is an orifice effect is exhibited based on a fluid action such as a resonance action of the fluid through the orifice passage.

  By the way, in the engine mount for automobiles, vibrations having different frequency ranges and amplitudes are input depending on the running state of the automobile, and therefore, vibration isolation performance is required for a plurality of different vibrations. In such vibration-proof performance, as conventionally known, “low-frequency large-amplitude engine shake corresponding to the rigid primary vibration of the engine” in the running state and “high-frequency small amount corresponding to the engine explosion main component in the stopped state”. "Amplitude idling vibration" is emphasized. In addition to these engine shakes and idling vibrations, there are cases in which measures against running-over noise against minute amplitude vibrations in a higher frequency range, which corresponds to road noise during traveling, may be considered. Specifically, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 09-310732), as an orifice passage, a first orifice passage tuned to engine shake and a second orifice tuned to idling vibration are used. Adopting a third orifice passage tuned to the passage and traveling noise, the movable member can be displaced in the opening part of the pressure receiving chamber side or the equilibrium chamber side in the second orifice passage and the third orifice passage. At the same time, a structure in which the third orifice passage is switched between the communication state and the cutoff state by the switching means has been proposed and studied.

  However, as a result of further studies by the present inventor, in the power unit of an automobile, the idling basic vibration (primary vibration, secondary vibration, etc. depending on the vehicle) that is a periodic vibration generated when the engine explodes during idling. In some cases, vibrations with a large amplitude may occur irregularly in a frequency range lower than the amplitude of the above-mentioned amplitude, and this is a major problem in reducing the ride comfort of the vehicle. As for amplitude vibration, it is practically difficult to identify with engine shake due to differences in vibration frequency, etc., and it is difficult to take countermeasures with orifice passages tuned to shake vibration, and idling due to differences in amplitude. It was newly found that even an orifice passage tuned to the fundamental vibration is difficult to take measures.

Japanese Patent Laid-Open No. 09-310732

  Here, the present invention has been made in the background as described above, and the problem to be solved is that, in the idling state, in addition to the idling fundamental vibration having a high frequency and a small amplitude, the frequency is lower than the idling fundamental vibration. To provide a fluid-filled engine mount for automobiles having a novel structure that can improve vehicle ride comfort by obtaining effective vibration-proof characteristics even for large-amplitude vibrations generated in the region. is there.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, the feature of the present invention is that the main rubber elastic body includes a first attachment member attached to one of a power unit of an automobile and a vehicle body, and a second attachment member attached to the other of the power unit and the vehicle body. Connected to form a pressure receiving chamber with a part of the wall made of rubber elastic body and an equilibrium chamber with a part of the wall made of flexible membrane, and uncompressed into the pressure receiving chamber and the equilibrium chamber In a fluid-filled engine mount for automobiles that contains an orifice passage that encloses a fluid and communicates the pressure-receiving chamber and the equilibrium chamber with each other. For the shake, the orifice passage is tuned to a low frequency range corresponding to the engine shake. Orifice passage, orifice passage for idling tuned to a high frequency range equivalent to idling basic vibration, and for shake A medium frequency orifice passage tuned to a frequency range higher than the tuning frequency of the refis passage and lower than a tuning frequency of the idling orifice passage is provided, and both openings of the idling orifice passage and the medium frequency orifice passage in the pressure receiving chamber are provided. An elastically deformable partition wall that covers the idling orifice passage and the equilibration chamber is further provided so as to cover the opening portion of the idling orifice passage in the equilibration chamber. A fluid-filled engine mount for automobiles provided with an elastic membrane.

  In such a fluid-filled engine mount for an automobile having a structure according to the present invention, when an engine shake in a low frequency region is input under running conditions, a relative pressure fluctuation occurs between the pressure receiving chamber and the equilibrium chamber. The fluid flow action is generated between the two chambers through the shaking orifice passage. Here, when the engine shake is input, the amount of fluid flowing through the pressure receiving chamber side openings in the medium frequency orifice passage and the idling orifice passage is sufficiently limited by the flow restricting member. Accordingly, the medium frequency in the pressure receiving chamber and the pressure leakage through each pressure receiving chamber side opening of the idling orifice passage are suppressed, and the fluid flow amount in the shake orifice passage is sufficiently ensured. The vibration-proofing effect (high damping effect) based on the fluid action of can be obtained stably.

  Also, when idling fundamental vibrations with a high frequency and a small amplitude corresponding to the main explosion component of the engine are input under idling conditions, the shake orifice path tuned to a lower frequency range is anti-resonant. As a result, the fluid flow action through the shaking orifice passage cannot function effectively. On the other hand, when the basic idling vibration is input, the fluid flow amount restriction function by the flow restricting member is prevented from working in the medium frequency orifice passage and the idling orifice passage, so that both orifice passages are substantially connected to the pressure receiving chamber. The fluid flow resistance of these pressure receiving chamber side openings is made sufficiently small so that they are opened. Here, since the medium frequency orifice passage is tuned to a frequency lower than the idling fundamental vibration, the fluid flow action cannot function effectively due to the anti-resonance action. Therefore, based on the desired deformation action of the partition elastic membrane, a fluid action such as a resonance action of the fluid between the pressure receiving chamber and the equilibrium chamber through the idling orifice passage is effectively generated, and the idling fundamental vibration is prevented. An effective anti-vibration effect (vibration insulation effect due to low dynamic springs) can be exhibited.

  Therefore, in a power unit of an automobile, a large amplitude vibration may occur irregularly at a lower frequency range than an idling basic vibration during idling. However, according to the fluid-filled engine mount having the structure according to the present invention, such a large amount of vibration is generated. Anti-vibration measures against amplitude vibration can be effectively achieved.

  That is, in the fluid-filled engine mount of this structure, the medium frequency orifice passage tuned to a higher frequency range than the engine shake and lower frequency range than the idling fundamental vibration is provided, so that the above-described idling can be performed. The large amplitude vibration that occurs irregularly in the lower frequency range than the idling fundamental vibration is set as the tuning vibration of the medium frequency orifice passage as the medium frequency large amplitude vibration having the frequency located between the engine shake and the idling fundamental vibration. obtain. Here, when the medium frequency large amplitude vibration is input, the fluid flow action of the shake orifice passage cannot function effectively due to anti-resonance. Further, if the above-described flow restricting member is designed to release the flow restricting function in order to secure the fluid flow rate in the medium frequency orifice passage, the idling orifice passage together with the medium frequency orifice passage is substantially free from the pressure receiving chamber. In the idling orifice passage designed for the purpose of vibration isolation by a low dynamic spring, the pressure change that can be accommodated by elastic deformation of the bulkhead elastic membrane against large amplitude vibration during idling Since the amount is exceeded, an effective fluid flow action cannot be obtained. In short, for the input of large amplitude vibrations that occur in the lower frequency range than the idling fundamental vibration in the idling state in question, for the purpose of shaking or idling in the pressure-receiving chamber that impairs the desired fluid flow rate of the medium frequency orifice passage Therefore, the fluid leakage action such as the resonance action of the fluid between the pressure receiving chamber and the equilibrium chamber through the medium frequency orifice passage is effectively generated, and the idling is greatly suppressed. An excellent anti-vibration effect (high damping effect) against amplitude vibration can be exhibited.

  In particular, in this structure, the partition elastic membrane is provided at the opening of the equilibrium chamber of the idling orifice passage so as to partition the equilibrium chamber and the idling orifice passage, so that the balance membrane is more balanced than the flow rate limiting member of the passage. It can be utilized as a chamber wall spring tuning means. That is, when tuning the wall spring stiffness of the equilibrium chamber including the composite spring of the partition elastic membrane and the flexible membrane, the spring stiffness of the partition elastic membrane is made larger than the spring stiffness of the flexible membrane, The pressure difference between the pressure receiving chamber and the equilibrium chamber is increased when engine shake or medium frequency large amplitude vibration is input to effectively obtain a high damping effect by the shake orifice passage and medium frequency orifice passage, and pressure is received when idling basic vibration is input. A structure that effectively reduces the pressure difference between the chamber and the equilibrium chamber and effectively obtains the vibration insulation effect based on the low dynamic spring characteristics by the idling orifice passage can be realized in one equilibrium chamber. In other words, it has the same effect as the mount structure with equilibration chambers for the shaker, medium frequency orifice passage, and idling orifice passage, so the structure can be simplified and the structure can be simplified. Can be achieved.

  Further, the tuning of the orifice passage may be performed by, for example, the body rubber elastic body or the flexible film corresponding to the rigidity of the wall springs of the pressure receiving chamber and the equilibrium chamber, that is, the amount of pressure change required to change each chamber by a unit volume. It can be suitably realized by changing the design of the passage length and passage cross-sectional area of the orifice passage and the flow restricting member while considering the characteristic values based on the respective elastic deformation amounts of the partition elastic membrane and the like. Therefore, as described above, the partition elastic membrane that can be used together with the flexible membrane as a suitable wall spring tuning means of the equilibrium chamber is provided at the opening of the equilibrium chamber of the idling orifice passage. When tuning the wall spring of the equilibrium chamber composed of the composite spring of the membrane and the partition elastic membrane, for example, as compared with the case where the partition elastic membrane is provided separately from the equilibrium chamber side opening of the idling orifice passage to the pressure receiving chamber side Further, it is not necessary to strictly consider the influence on the rigidity of the wall spring due to the opening from the equilibrium chamber side opening to the elastic rubber film in the idling orifice passage opening into the equilibrium chamber. As a result, the tuning change of the wall spring stiffness of the equilibrium chamber can be facilitated, and the tuning performance of the orifice passage for shaking, medium frequency, and idling can be improved. Thereby, for example, the frequency of the engine shake changes or the idling basic vibration changes from the primary vibration to the secondary vibration depending on the cylinder arrangement type such as L type and V type, the number of cylinders and other vehicle structures. Therefore, even if the frequency of vibration to be isolated is different, such as the frequency of large-amplitude vibration generated on the lower frequency side than the idling basic vibration, the tuning change of each orifice passage can be easily handled. Can be done.

  Therefore, according to the fluid-filled engine mount for automobiles of the present invention, in addition to being able to stably obtain vibration-proof characteristics against engine shake and idling basic vibration, in the idling state, lower frequency range than idling basic vibration. In this way, an effective vibration-proof characteristic can be obtained even for large-amplitude vibrations that occur irregularly, so that excellent vehicle riding comfort can be realized.

  That is, when the present inventor diligently studied the vibration isolating characteristics of a conventional engine mount for automobiles as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 09-310732) and the like, a lower frequency range than the idling basic vibration during idling. Large amplitude vibrations (medium frequency large amplitude vibrations) may occur at irregular intervals, and fluid flow action is not generated in the shake orifice passage tuned to a lower frequency range than such medium frequency large amplitude vibrations. In addition to being unable to function effectively, medium-frequency large-amplitude vibration is a mode close to the rigid body vibration of the engine. Therefore, the idling orifice passage designed for the purpose of vibration isolation with low dynamic springs originally is vibration-proof. The effect cannot function effectively, and the non-function of the anti-vibration effect by these orifice passages is great for the vehicle ride comfort. It has been found that has become a problem. Therefore, the present inventor needs a vibration damping effect by high damping rather than a vibration insulation effect by low dynamic spring for such medium frequency large amplitude vibration, and vibration by idling vibration is conventionally reduced by low dynamic spring. The conclusion that it would be difficult to cope with it unless the general idea of damping with the vibration insulation effect was reversed was reached, and the present invention was completed, and the damping effect could be improved. In short, the large-amplitude vibrations that occur irregularly during idling have not been considered in the past, and vibration suppression has not been realized. The present inventor has newly found that countermeasures should be taken, and the present invention has been completed based on such knowledge.

  Further, in the fluid-filled engine mount for automobiles according to the present invention, the movable plate is based on the pressure difference between the pressure receiving chamber and the equilibrium chamber in the portion covering both the opening portions of the idling orifice passage and the medium frequency orifice passage in the pressure receiving chamber. It is possible to adopt a structure in which the flow rate restricting member is configured by disposing it in a displaceable manner and disposing the displacement amount in a state where the displacement amount is restricted by contact with the restraining member. According to such a structure, in the idling state, the idling basic vibration that is constantly generated with the explosion of the engine, the large amplitude vibration that is irregularly generated in a lower frequency range than the idling basic vibration, and the engine in the running state By utilizing the fact that the pressure difference between the pressure receiving chamber and the equilibrium chamber is different under each input such as a shake, the flow restriction of the idling and medium frequency orifice passages can be advantageously realized.

  That is, the amplitude of the high-frequency small-amplitude vibration corresponding to the idling fundamental vibration is sufficiently smaller than the amplitude of the low-frequency large-amplitude vibration corresponding to the engine shake. In addition, the magnitude relationship between the amplitude of the medium-frequency large-amplitude vibration corresponding to the large-amplitude vibration in the lower frequency range than the idling basic vibration during idling and the amplitude of the engine shake is not simply compared. Depending on the cylinder arrangement type such as the type, the number of cylinders, and other vehicle structures, it is assumed that the magnitude relationship may be reversed or the same. The present invention can be suitably applied to an automobile engine mount in which the amplitude of the amplitude vibration is smaller than the amplitude of the engine shake. Therefore, when idling basic vibration or medium frequency large amplitude vibration is input, the pressure difference between the pressure receiving chamber and the equilibrium chamber is not so large compared to the input of the engine shake. A mode in which the restraint displacement of the movable plate due to contact with the movable plate is avoided and the fluid flow action of the idling and medium frequency orifice passages is sufficiently ensured based on the small displacement due to the deformation of the movable plate is suitably realized. obtain. Further, according to this structure, the movable plate can also be employed as a wall spring tuning means for the pressure receiving chamber, whereby the tuning performance in the medium frequency orifice passage and the idling orifice passage can be further improved. .

  On the other hand, when a low-frequency large-amplitude vibration equivalent to an engine shake is input, the pressure difference between the pressure receiving chamber and the equilibrium chamber becomes large, and the movable plate is greatly displaced and brought into contact with the restraining member, so that the movable plate is restrained. Displaced. As a result, the pressure-receiving chamber side openings of the idling and medium frequency orifice passages are substantially covered with the movable plate, and the fluid flow action of the idling and medium frequency orifice passages is restricted so as not to function effectively. The aspect can be suitably realized.

  Further, in the fluid-filled engine mount for an automobile according to the present invention, a partition member that partitions the pressure receiving chamber and the equilibrium chamber is provided, and the shaker orifice passage is formed so as to extend in the circumferential direction of the outer peripheral portion of the partition member. In the central part of the partition member, the flow restricting member is disposed so as to face the pressure receiving chamber, and the partition elastic membrane is disposed so as to face the equilibrium chamber, and the idling is performed between the flow restricting member and the partition elastic membrane in the partition member. A structure in which a medium-frequency orifice passage is formed so as to extend around the partition elastic membrane between the flow restricting member and the portion facing the equilibrium chamber in the partition member may be employed.

  According to such a structure, since the shaker orifice passage is formed in the outer peripheral portion of the partition member, the passage length can be sufficiently secured and the flow resistance of the fluid is easily set to be low, and the low frequency vibration Therefore, it is easier to obtain the anti-vibration effect (high damping effect) required for the engine shake. Further, since the flow restricting member and the partition elastic membrane are formed in the central portion of the partition member, the partition member can ensure a large effective area of the flow restricting member and the partition elastic membrane, It is easy to secure a large cross-sectional area of the medium-frequency orifice passage, so that the vibration-proofing effect against the desired basic idling vibration (vibration insulation effect by low dynamic springs) and the vibration prevention against medium-frequency large-amplitude vibration during idling The effect (high damping effect) can be exhibited more advantageously.

  Further, in the fluid-filled engine mount for automobiles according to the present invention, the second mounting member has a cylindrical portion, and the first mounting member is arranged separately on one opening side of the cylindrical portion. By elastically connecting with the main rubber elastic body, one opening of the cylindrical portion is fluid-tightly closed, and a flexible film is disposed on the other opening side of the cylindrical portion to provide the other end of the cylindrical portion. The opening is closed fluid-tightly with a flexible membrane, the partition member is assembled inside the tubular portion, and the region between the main rubber elastic body and the flexible membrane inside the tubular portion is partitioned by the partition member. Thus, a structure in which the pressure receiving chamber and the equilibrium chamber are formed on both sides of the partition member may be employed. According to such a structure, the pressure receiving chamber and the equilibrium chamber can be realized with a simple structure, and downsizing and reduction in manufacturing cost can be achieved.

  Hereinafter, in order to clarify the present invention more specifically, an embodiment of the present invention will be described in detail with reference to the drawings. First, FIG. 1 shows an automobile engine mount 10 as an embodiment of the fluid-filled engine mount for automobiles of the present invention. In this automobile engine mount 10, a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member are elastically connected to each other by a main rubber elastic body 16. The first mounting bracket 12 is attached to a vehicle power unit (not shown), and the second mounting bracket 14 is attached to a vehicle body (not shown) of the vehicle, so that the power unit is protected from the vehicle body via the vehicle engine mount 10. It is designed to be supported.

  In FIG. 1, the state of the vehicle engine mount 10 alone before being mounted on the vehicle is shown, but in the mounted state on the vehicle, the shared support load of the power unit is in the mount axis direction (in FIG. 1), the first mounting bracket 12 and the second mounting bracket 14 are displaced toward each other in the mount axis direction, and the main rubber elastic body 16 is elastically deformed. In addition, under such a mounted state, main vibrations to be vibrated are input substantially in the mount axis direction. In the following description, unless otherwise specified, the vertical direction refers to the vertical direction in FIG.

  More specifically, the first mounting member 12 has a substantially truncated truncated cone shape or a cylindrical shape with a small diameter. A screw hole 18 that opens to the upper end surface is formed in the central portion in the direction perpendicular to the axis of the first mounting bracket 12, and a member on the power unit side (not shown) is screwed and fixed to the screw hole 18 via a fixing bolt. Thus, the first mounting member 12 is attached to the power unit.

  Further, the second mounting bracket 14 has a large-diameter substantially stepped cylindrical shape, and a step portion 20 spreading in an annular shape in a direction perpendicular to the axis at an intermediate portion in the axial direction, and an outer peripheral edge portion of the step portion 20 The large-diameter cylindrical portion 22 having a large-diameter cylindrical shape that extends upward from the inner periphery and the small-diameter cylindrical portion 24 that extends downward from the inner peripheral edge of the step portion 20 and has a smaller diameter than the large-diameter cylindrical portion 22 are configured. That is, the second mounting bracket 14 of the present embodiment constitutes a cylindrical portion substantially in its entirety. The second mounting bracket 14 is attached to a vehicle body side member via a bracket member (not shown). The first mounting bracket 12 and the second mounting bracket 14 are arranged on the same central axis, and the first mounting bracket 12 is an opening portion of the large-diameter cylindrical portion 22 of the second mounting bracket 14. It is positioned at a predetermined distance above the distance. A main rubber elastic body 16 is interposed between the first mounting bracket 12 and the second mounting bracket 14.

  The main rubber elastic body 16 is a thick rubber elastic body having a substantially truncated truncated cone shape as a whole, and the substantially entire portion excluding the upper end portion of the first mounting member 12 is embedded in the upper end portion thereof. In addition, the entire inner peripheral surface of the large-diameter cylindrical portion 22 and the upper end surface of the stepped portion 20 of the second mounting bracket 14 are vulcanized and bonded to the outer peripheral surface of the main rubber elastic body 16. Has been. In short, the main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting bracket 12 and the second mounting bracket 14, whereby the first mounting bracket 12 and the second mounting bracket are formed. 14 is connected by a main rubber elastic body 16, and one opening (in FIG. 1) of the second mounting bracket 14 is fluid-tightly closed by the main rubber elastic body 16. In addition, a substantially inverted mortar-shaped large-diameter recess 26 that opens downward is formed on the lower end surface of the main rubber elastic body 16. Further, the main rubber elastic body 16 is integrally formed with a thin seal rubber layer 28 extending downward from the opening edge of the large-diameter recess 26, and the inner peripheral surface of the small-diameter cylindrical portion 24 of the second mounting bracket 14. Is formed on the substrate. Furthermore, at the boundary between the opening edge of the large-diameter recess 26 and the seal rubber layer 28, the inner side is perpendicular to the seal rubber layer 28 and the outer side of the large-diameter recess 26 is axially perpendicular to the opening edge. A stepped portion 30 is formed that extends in an annular shape in the direction perpendicular to the axis.

  A partition member 32 is assembled to such an integrally vulcanized molded product of the main rubber elastic body 16. The partition member 32 has a substantially circular block shape as a whole, and is formed using a hard member made of a metal material, a synthetic resin material, or the like. The partition member 32 includes a partition member main body 34, a first lid member 36, a second lid member 38, and a support ring 40.

  The partition member main body 34 has a substantially circular block shape, and a central flow path 42 extending in a substantially constant circular cross section in the axial direction that is the thickness direction of the partition member 32 is formed in a substantially central portion in the direction perpendicular to the axis. In addition, the upper end and the lower end of the central flow path 42 have a substantially circular concave shape having a larger diameter than the central flow path 42, and are formed on the upper end surface and the lower end surface of the partition member body 34. An upper fitting recess 44 and a lower fitting recess 46 that are open are formed. That is, the central channel 42 and the upper and lower fitting recesses 44 and 46 are formed through the central portion in the direction perpendicular to the axis of the partition member main body 34 having a circular block shape. In other words, it has a thick, generally cylindrical shape with a large thickness dimension in the direction perpendicular to the axis.

  A first circumferential groove 48 and a second circumferential opening that open to the outer circumferential surface of the partition member main body 34 and extend in the circumferential direction with a length of a little less than one round are respectively formed in the axial upper end portion and the axial middle portion of the outer peripheral portion of the partition member main body 34. A circumferential groove 50 is formed. The first circumferential groove 48 is also formed at the upper edge of the partition member main body 34 so that it also opens at the upper end surface of the partition member main body 34. In addition, between the first circumferential groove 48 and the second circumferential groove 50 at one end in the circumferential direction, an opening is formed on the outer circumferential surface of the partition member main body 34 in the same manner as the first and second circumferential grooves 48 and 50. A connecting groove 51 is formed by inclining the partition member body 34 in the circumferential direction or extending in the axial direction, and the first circumferential groove 48 and the second circumferential groove 50 are connected to each other via the connecting groove 51. Yes. That is, the first circumferential groove 48, the second circumferential groove 50, and the connection groove 51 cooperate with each other so that the outer peripheral portion of the partition member main body 34 is spirally extended in the circumferential direction with a length of a little less than two rounds. A groove is formed. Further, at one place or a plurality of places on the circumference of the second circumferential groove 50, an inner connection flow in which the partition member main body 34 extends in a tunnel shape in a direction perpendicular to the axis and the second circumferential groove 50 and the central flow path 42 communicate with each other. A path 52 is formed.

  The first lid member 36 has a shallow, substantially bottomed cylindrical shape in which the axial dimension of the peripheral wall portion is small, and the outer diameter thereof is the inner diameter of the upper fitting recess 44 of the partition member main body 34. The axial dimension is made substantially the same as the axial dimension of the upper fitting recess 44. Further, a first through hole 54 as a through hole made up of a plurality of small holes is formed through the bottom wall portion of the first lid member 36.

  Further, the second lid member 38 has a thin and substantially disk shape, and the outer diameter dimension thereof is substantially the same as the outer diameter dimension of the partition member main body 34. Further, a second through hole 56 as a through hole made up of a plurality of small holes is formed through the central portion of the second lid member 38 in the direction perpendicular to the axis.

  The peripheral wall portion of the first lid member 36 is fitted and fixed to the peripheral wall portion of the upper fitting recess 44 of the partition member main body 34 by press fitting or the like, and the lower end portion of the peripheral wall portion of the first lid member 36 and the outer peripheral portion of the bottom portion. Is superimposed on the bottom of the upper fitting recess 44 in the axial direction. In addition, the second lid member 38 is positioned substantially concentrically with the partition member main body 34, and is overlapped with the upper end surface of the partition member main body 34 and the upper end surface of the first lid member 36 in the axial direction. A fixing member such as a bolt or a rivet (not shown) penetrates through the first lid member 36 and is fixed to the partition member main body 34 and the like in the overlapping portion with 34 and the like.

  As a result, the first lid member 36 and the second lid member 38 are fixed to the central portion of the upper part of the partition member main body 34 in the axis-perpendicular direction so as to be positioned substantially concentrically with each other. The upper opening portion of the circumferential groove 48 is covered with the outer peripheral portion of the second lid member 38. The upper end portion of the central flow path 42 of the partition member main body 34 is covered with the first and second lid members 36 and 38, and the opening portion of the first lid member 36 is the axis of the second lid member 38. By covering with the central portion in the perpendicular direction, the upper end surface of the bottom portion of the first lid member 36, the inner peripheral surface of the peripheral wall portion, and the second lid member 38 are formed on the upper portion of the central portion in the direction perpendicular to the axis of the partition member 32. A housing cavity 58 extending in a substantially constant circular cross section in the axial direction is formed in cooperation with the lower end surfaces of the two. That is, the top wall portion of the accommodation space 58 is configured to cover the opening of the first lid member 36 in the second lid member 38, and the bottom wall portion of the accommodation space 58 is the first lid member 36. It is comprised by the bottom part, and the surrounding wall part of the accommodation space 58 is further comprised by the surrounding wall part of the 1st cover member 36. FIG. Here, before the opening portion of the first lid member 36 is covered with the second lid member 38 to form the accommodation space 58, the elastic rubber plate 60 as a movable plate is placed in the first lid member 36. The elastic rubber plate 60 is accommodated in the accommodating space 58 by configuring the accommodating space 58 as described above.

  The elastic rubber plate 60 is made of a rubber elastic material and has a disk shape whose thickness dimension is substantially constant throughout. The axial dimension of the housing space 58 is expressed by the thickness dimension of the elastic rubber plate 60 extending in the axial direction expressed by the distance between the bottom surface of the first lid member 36 and the opposed surface of the second lid member 38 in the axial direction. It is made smaller by a predetermined amount than Further, the outer diameter of the elastic rubber plate 60 is slightly smaller than the inner dimension in the direction perpendicular to the axis of the housing space 58 represented by the inner diameter of the peripheral wall portion of the first lid member 36. Thereby, the elastic rubber plate 60 is accommodated in the accommodating space 58 in a state where displacement in the axial direction is mainly allowed.

  Further, the support ring 40 has a large-diameter, generally circular ring shape as a whole. In particular, the central portion in the width direction extending in the direction perpendicular to the axis includes an outer peripheral surface extending in a cylindrical shape in the axial direction, and the upper end portion of the cylindrical outer peripheral surface extends in an annular shape on the inner side in the width direction ( The lower end portion of the cylindrical outer peripheral surface is a lower end portion (surface) that spreads in an annular shape outward in the width direction. The cylindrical outer peripheral surface (part) of the support ring 40 is press-fitted and fixed to the peripheral wall portion of the lower fitting recess 46 of the partition member main body 34, and the upper end surface of the outer peripheral portion of the support ring 40 is in the partition member main body 34. It overlaps with the lower end surface around the opening edge of the lower fitting recess 46 in the axial direction.

  Here, an elastic rubber film 62 as a partition elastic film is sandwiched between the partition member main body 34 and the support ring 40. The elastic rubber film 62 is made of a rubber elastic material and has a substantially disc shape. Further, the outer peripheral portion including the outer peripheral edge portion of the elastic rubber film 62 extends in the circumferential direction with a circular cross section or the like projecting larger in the thickness direction than the central portion, so that it is thicker than the central portion. ing. The upper end surface of the outer peripheral portion of the elastic rubber film 62 is superimposed on the bottom surface of the lower fitting recess 46 of the partition member main body 34, and the lower end surface of the outer peripheral portion of the elastic rubber film 62 is the upper end surface of the support ring 40. Based on the press-fit fixing force between the support ring 40 and the partition member body 34, the outer peripheral portion of the elastic rubber film 62 is sandwiched between and supported by the partition member body 34 and the support ring 40 while being compressed and deformed. Yes. Thereby, the elastic rubber film 62 is assembled to the lower side of the central portion in the direction perpendicular to the axis of the partition member 32 while allowing deformation of the central portion thereof, and the lower end portion of the central flow path 42 of the partition member main body 34. However, the elastic rubber film 62 is fluid-tightly closed.

  The partition member 32 in which the elastic rubber plate 60 and the elastic rubber film 62 are assembled is inserted in the axial direction from the lower opening of the second mounting bracket 14 in the integrally vulcanized molded product of the main rubber elastic body 16, An outer peripheral portion of the second lid member 38 in the partition member 32 is overlapped with the step portion 30 of the main rubber elastic body 16 in the axial direction. In addition, a diaphragm 64 as a flexible film is assembled to the lower opening of the second mounting bracket 14.

  The diaphragm 64 is formed of a thin circular rubber film having sufficient slackness. The outer peripheral edge of the diaphragm 64 is vulcanized and bonded to the inner peripheral surface of a fixing metal fitting 66 having a large-diameter cylindrical shape as a fixing member. The fixing bracket 66 is inserted in the axial direction from the lower opening of the second mounting bracket 14, and the upper end portion of the fixing bracket 66 is the outer periphery of the partition member 32 constituted by the support ring 40 or the partition member body 34. It is overlapped with the lower end of the side in the axial direction.

  Then, the second mounting bracket 14 is subjected to diameter reduction processing such as an eight-way drawing, and along with the diameter reduction deformation of the second mounting bracket 14, on the inner peripheral surface of the small diameter cylindrical portion 24 of the second mounting bracket 14. The adhered seal rubber layer 28 is superimposed on the outer peripheral surfaces of the partition member 32 and the fixing bracket 66 while being compressed and deformed between the second mounting bracket 14 and the partition member 32 and the fixing bracket 66. Thus, the partition member 32 and the fixing metal fitting 66 are fitted and fixed to the second attachment metal fitting 14, and the lower opening of the second attachment metal fitting 14 is fluid-tightened by the diaphragm 64 including the fixing metal fitting 66. The region between the main rubber elastic body 16 and the diaphragm 64 inside the second mounting member 14 is divided into two fluid-tight by a partition member 32 while being closed.

  On one side in the axial direction (on the upper side in FIG. 1) sandwiching the partition member 32, a part of the wall portion is in a region where the large-diameter recess 26 of the main rubber elastic body 16 is closed by the partition member 32. A pressure receiving chamber 68 is formed which is composed of the main rubber elastic body 16 and in which pressure fluctuation is generated based on elastic deformation of the main rubber elastic body 16 when vibration is input. Further, on the other side in the axial direction with respect to the partition member 32 (lower side in FIG. 1), a part of the wall portion is formed by the diaphragm 64 in the region between the partition member 32 and the diaphragm 64. An equilibrium chamber 70 in which a volume change is easily allowed based on elastic deformation is formed. The pressure receiving chamber 68 and the equilibrium chamber 70 are filled with an incompressible fluid. For example, water, alkylene glycol, polyalkylene glycol, silicone oil, or the like is employed as the incompressible fluid to be enclosed. In order to effectively obtain a vibration isolation effect based on a fluid action such as a resonance action of the fluid. It is desirable to employ a low viscosity fluid of 0.1 Pa · s or less. Further, the incompressible fluid is sealed in the pressure receiving chamber 68 and the equilibrium chamber 70, for example, the partition member 32 for the integrally vulcanized molded product of the main rubber elastic body 16 including the first and second mounting brackets 12 and 14. And the fixing metal fitting 66 of the diaphragm 64 is preferably realized by performing the assembly in an incompressible fluid.

  Further, as described above, the seal rubber layer 28 of the second mounting bracket 14 is superimposed on the outer peripheral surface of the partition member 32 while being compressed and deformed between the second mounting bracket 14 and the partition member 32. The openings of the first circumferential groove 48, the second circumferential groove 50, and the connection groove 51 on the outer circumferential surface of the member 32 are covered with a sealing rubber layer 28 in a fluid-tight manner. Thereby, the first outer peripheral flow path 72 formed by the cooperation of the first circumferential groove 48 and the second mounting bracket 14 at the upper end portion in the axial direction and the intermediate portion in the axial direction in the outer peripheral portion of the partition member 32, and the second A second outer peripheral flow path 74 formed by cooperation of the circumferential groove 50 and the second mounting bracket 14 is formed so as to extend in a tunnel shape with a length of slightly less than one round in the circumferential direction. Furthermore, the outer connection flow path 76 formed by the cooperation of the connection groove 51 and the second mounting bracket 14 causes one end of the first outer peripheral flow path 72 in the circumferential direction and the second outer peripheral flow path 74 in the circumferential direction. One end is connected to each other.

  Here, the shaker orifice passage 78 of the present embodiment includes the first outer peripheral flow path 72, the second outer peripheral flow path 74, and the outer connection flow path 76, so that the outer peripheral portion of the partition member 32 is It extends in a spiral shape with a length of less than two rounds in the circumferential direction. One end of the shaker orifice passage 78 is connected to the pressure receiving chamber 68 through a communication hole 80 penetrating the second lid member 38 located at the other circumferential end of the first outer peripheral flow path 72. At the same time, the other end of the shake orifice passage 78 penetrates the lower end of the partition member main body 34 located at the other end in the circumferential direction of the second outer peripheral flow path 74, and the support ring 40 further extends to the lower end. When the outer peripheral portions of the two are superposed, they are connected to the equilibrium chamber 70 through a communication hole 82 penetrating the outer peripheral portion. Thereby, fluid flow through the shake orifice passage 78 between the pressure receiving chamber 68 and the equilibrium chamber 70 is allowed.

  Further, the central flow path 42 formed in the central portion of the partition member 32 is accommodated in the accommodating space 58 constituted by the first and second lid members 36 and 38 in the axial direction of the automobile engine mount 10. The elastic rubber plate 60 is positioned opposite the pressure receiving chamber 68, and the elastic rubber film 62 is positioned opposite the equilibrium chamber 70. In the elastic rubber plate 60, the pressure of the pressure receiving chamber 68 is applied to one surface (the upper side in FIG. 1) through the second through hole 56 of the second lid member 38, and the other side. The pressure in the equilibrium chamber 70 is applied to the surface (lower in FIG. 1) through the first through hole 54 of the first lid member 36 through the pressure transmission of the central flow path 42 due to the elastic deformation of the elastic rubber film 62. Further, the pressure in the equilibrium chamber 70 is exerted from the central flow path 42, the inner connection flow path 52, and the second outer peripheral flow path 74 through a communication hole 88 formed in the partition member 32 described later. On the other hand, in the elastic rubber film 62, the pressure receiving chamber 68 has a surface (on the upper side in FIG. 1) of the pressure receiving chamber 68 through pressure transmission of the central flow path 42 due to deformation and displacement of the elastic rubber plate 60 in the accommodation space 58. A pressure is applied, and the pressure of the equilibrium chamber 70 is applied to the other surface (lower side in FIG. 1).

  Therefore, the elastic rubber plate 60 is deformed and displaced in the accommodation space 58 based on the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70, so that the central flow path 42 and the inner side between the pressure receiving chamber 68 and the equilibrium chamber 70 are changed. The fluid flow action through the connection flow path 52 and the second outer peripheral flow path 74 is effectively generated. Furthermore, in addition to the deformation displacement in the accommodation space 58 of the elastic rubber plate 60, the elastic rubber film 62 is effectively elastically deformed, so that the pressure between the pressure receiving chamber 68 and the equilibrium chamber 70 through the central flow path 42. The fluid flow action is effectively generated. In other words, the elastic rubber plate 60 abuts against the bottom portion of the first lid member 36 constituting the bottom wall portion of the accommodation space 58 or the central portion of the second lid member 38 constituting the top wall portion of the accommodation space 58. As a result, the first through-hole 54 or the second through-hole 56 is blocked by the elastic rubber plate 60 or the elastic rubber film 62 does not cause the desired elastic deformation, so that the fluid in the central channel 42 The fluid action cannot function effectively. Further, the elastic rubber plate 60 is brought into contact with the bottom portion of the first lid member 36 and the central portion of the second lid member 38 so that the first through hole 54 and the second through hole 56 are closed, whereby the central flow path is formed. Therefore, the fluid flow action through 42, the inner connection flow path 52, and the second outer peripheral flow path 74 cannot function effectively.

  Therefore, the idling orifice passage 84 of the present embodiment is constituted by the central flow path 42 of the partition member 32. In particular, the opening on the pressure receiving chamber 68 side of the idling orifice passage 84 includes the accommodation space 58 of the partition member 32 and the first and second through holes 54, 56. It is formed in a state covered with. Further, the opening on the equilibrium chamber 70 side of the idling orifice passage 84 is formed by the lower fitting recess 46 of the partition member 32 and is fluid-tightly closed by the elastic rubber film 62.

  Further, the medium frequency orifice passage 86 of the present embodiment includes a part of the circumference extending with a length less than the entire central flow path 42, inner connection flow path 52, and second outer peripheral flow path 74 of the partition member 32. It consists of Here, the opening on the pressure receiving chamber 68 side of the medium frequency orifice passage 86 includes the accommodation space 58 of the partition member 32 and the first and second through holes 54 and 56, similarly to the idling orifice passage 84. And formed in a state covered with the elastic rubber plate 60. Further, the opening on the equilibrium chamber 70 side of the intermediate frequency orifice passage 86 is provided in the lower end portion of the partition member main body 32 excluding the portion where the communication hole 82 is formed in the second outer peripheral flow path 74, and further on the lower end portion. When the outer peripheral part of the support ring 40 is overlapped, it is constituted by a communication hole 88 penetrating through the outer peripheral part, and is connected to the equilibrium chamber 70 through the communication hole 88.

  That is, as the functional model diagram of the automobile engine mount 10 of this embodiment is also shown in FIG. 2, as the orifice passage for communicating the pressure receiving chamber 68 and the equilibrium chamber 70, the shaker orifice passage 78 and the idling passage are used. The orifice passage 84 and the medium frequency orifice passage 86 are employed. In particular, in this embodiment, the shake orifice passage 78 and the medium frequency orifice passage 86 are configured to share the second outer peripheral passage 74. The intermediate frequency orifice passage 86 and the idling orifice passage 84 are configured to share the central flow path 84.

  A shake orifice passage 78 is formed so as to extend in the circumferential direction on the outer peripheral portion of the partition member 32. Further, in the central portion of the partition member 32, the elastic rubber plate 60 is disposed so as to face the pressure receiving chamber 68 in a state where the elastic rubber plate 60 is accommodated in the accommodation space 58 formed by the first and second lid members 36 and 38. The elastic rubber film 62 is disposed so as to face the equilibrium chamber 70, and the idling is performed by the central flow path 42 extending in the mount axis direction between the elastic rubber plate 60 and the elastic rubber film 62. An orifice passage 84 is formed. Furthermore, an intermediate frequency orifice passage 86 is formed so as to extend around the elastic rubber film 62 between the elastic rubber plate 60 in the partition member 32 and the lower end portion facing the equilibrium chamber 70.

  As a result, in the portion that covers both openings of the idling orifice passage 84 and the medium frequency orifice passage 86 in the pressure receiving chamber 68, the accommodation space in which the elastic rubber plate 60 is constituted by the first and second lid members 36 and 38. 58, the elastic rubber plate 60 is accommodated and disposed in the first and second cover members 36 and 38. The pressure receiving chamber 68 is provided through the first and second through holes 54 and 56 of the first and second lid members 36 and the accommodating space 58. Based on the pressure difference between the balance chamber 70 and the balance chamber 70, the inside of the accommodation space 58 can be displaced, and the displacement amount of the elastic rubber plate 60 is limited by contacting the first or second lid member 36, 38. At the same time, the first or second through holes 54 and 56 are covered with the elastic rubber plate 60, so that the amount of each fluid allowed to flow through the idling orifice passage 84 and the medium frequency orifice passage 86 is reduced. It is adapted to be limited. As is clear from this, the restraining member for restraining the amount of displacement of the elastic rubber plate 60 includes the first and second lid members 36, 38, the idling and medium frequency orifice passages 84, The flow restricting member 86 that restricts the fluid flow amount 86 includes the elastic rubber plate 60, the first and second lid members 36 and 38, the first and second through holes 54 and 56, and the accommodation space 58. Yes.

  In the automobile engine mount 10 having such a structure, the resonance frequency of the fluid flowing through the shake orifice passage 78 is tuned to a low frequency range of about 10 Hz corresponding to the engine shake. Also, since the amplitude of the engine shake is large corresponding to the rigid primary vibration of the engine, the elastic rubber plate 60 is used for the first by utilizing the fact that the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 becomes large during the engine shake. Alternatively, the first or second through holes 54 and 56 are designed to be closed by the elastic rubber plate 60 by being brought into contact with the second lid members 36 and 38.

  As a result, when a low-frequency large-amplitude vibration corresponding to an engine shake is input under the traveling state of the automobile, the elastic rubber plate 60 is restrained and displaced by contact with the first or second lid member 36, 38. By closing the first or second through holes 54, 56, the fluid flow amount in the idling and medium frequency orifice passages 84, 86 is limited. Therefore, the pressure leakage through the idling of the pressure receiving chamber 68 and the medium frequency orifice passages 84 and 86 is suppressed, and the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 is effectively induced, and the fluid in the shake orifice orifice passage 78 is obtained. A sufficient amount of flow can be secured. Based on the resonance action of the fluid flowing through the shake orifice passage 78, an excellent anti-vibration effect (high damping effect) can be exhibited against the engine shake.

  In addition, the resonance frequency of the fluid that flows through the idling orifice passage 84 is tuned to a high frequency range of about 20 to 30 Hz corresponding to the idling basic vibration periodically generated with the explosion of the engine during idling. Further, since the amplitude of the idling basic vibration is sufficiently smaller than the amplitude of the engine shake described above, the idling basic vibration is input by utilizing the fact that the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 does not become so large. Sometimes, the elastic rubber plate 60 is designed to be positively displaced in the accommodation space 58 by suppressing the contact of the elastic rubber plate 60 with the first or second lid members 36 and 38. More desirably, the small displacement of the elastic rubber plate 60 can be generated more positively by tuning the resonance frequency of the elastic rubber plate 60 to a high frequency range corresponding to the idling fundamental vibration. In addition, by tuning the resonance frequency of the elastic rubber film 62 provided in the equilibrium chamber 70 side opening of the orifice passage 84 for idling to a high frequency range corresponding to the basic idling vibration, the elastic rubber film is input when the idling basic vibration is input. 62 may be positively elastically deformed.

  As a result, when a high-frequency small-amplitude vibration corresponding to the idling fundamental vibration is input in the idling state, the fluid flow resistance is significantly increased due to the anti-resonant action of the shaking orifice passage 78 and the substantially closed state is obtained. However, based on the small displacement caused by the deformation of the elastic rubber plate 60 in the accommodation space 58 and the elastic deformation of the elastic rubber film 62, the fluid flow action through the idling orifice passage 84 between the pressure receiving chamber 68 and the equilibrium chamber 70. The resonance effect is exhibited. Further, along with the small displacement of the elastic rubber plate 60 in the accommodation space 58, the medium frequency orifice passage 86 as well as the idling orifice passage 84 is substantially opened to the pressure receiving chamber 68. Since the tuning frequency 86 is set in a lower frequency range than the idling fundamental vibration, the medium frequency orifice passage 86 is substantially closed by an anti-resonant action. As a result, there is no possibility that the pressure in the pressure receiving chamber 68 leaks out through the medium frequency orifice passage 86, so that a pressure difference is effectively induced between the pressure receiving chamber 68 and the equilibrium chamber 70, and the elastic rubber plate 60 is small displaced. As a result, the fluid flow amount of the idling orifice passage 84 can be sufficiently secured based on the deformation of the elastic rubber film 62, and an effective anti-vibration effect (vibration insulation effect based on the low dynamic spring characteristics) can be exhibited against the idling basic vibration. obtain.

  By the way, as a result of investigation by the present inventor, it has been found that in the engine mount 10 for an automobile, a large amplitude vibration may be input aperiodically in an idling state at a frequency lower than the idling basic vibration. Further, it has been found that such large amplitude vibration is generated in a higher frequency range than the engine shake, and that the amplitude is sufficiently larger than the amplitude of the high frequency vibration corresponding to the idling basic vibration. In such a case, the shaker orifice passage 78 is substantially closed due to the anti-resonance action, and the idling orifice passage 86 designed for the purpose of vibration isolation by the low dynamic spring is elastic. Since the amount of pressure change that can be dealt with when the rubber film 62 is deformed is exceeded, the fluid flow action cannot function effectively.

  Therefore, in the automobile engine mount 10 according to the present embodiment, the resonance frequency of the fluid that flows through the medium frequency orifice passage 86 is large amplitude vibration that is generated in a lower frequency range than the idling fundamental vibration in the idling state in question. Is tuned to a medium frequency range of about 11 to 15 Hz corresponding to medium frequency large amplitude vibration. Further, the amplitude of the medium frequency large amplitude vibration is made smaller than the amplitude of the engine shake described above, and the fact that the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 does not become so large, the medium frequency large amplitude vibration. Is designed so that the elastic rubber plate 60 can be slightly displaced in the accommodation space 58 by suppressing the contact of the elastic rubber plate 60 with the first or second lid members 36 and 38.

  Therefore, when medium-frequency large-amplitude vibration is input during idling, the fluid passing through the medium-frequency orifice passage 86 between the pressure receiving chamber 68 and the equilibrium chamber 70 is based on the deformation displacement of the elastic rubber plate 60 in the accommodation space 58. A resonance action which is a fluid action can be effectively exhibited. Therefore, an effective anti-vibration effect (high damping effect) can be exhibited even for large-amplitude vibrations that occur irregularly during such idling, and excellent vehicle riding comfort can be realized.

  In particular, the tuning of the shake orifice passage 78, the medium frequency orifice passage 84, and the idling orifice passage 86 in this embodiment is performed by adjusting the rigidity of the wall springs of the pressure receiving chamber 68 and the equilibrium chamber 70, that is, the chambers 68 and 70 by a unit volume. The passage length and passage cross-sectional area of each of the orifice passages 78, 84, 86 are taken into consideration while considering the characteristic values based on the respective elastic deformation amounts of the main rubber elastic body 16 and the diaphragm 64 corresponding to the amount of pressure change required for changing. Is done by adjusting. The tuning frequency of the orifice passages 78, 84, and 86 is a frequency at which the phase of pressure fluctuation transmitted through the orifice passages 78, 84, and 86 changes to bring about a substantially resonant state.

  Here, in the present embodiment, the elastic rubber film 62 is provided in the opening of the equilibrium chamber 70 of the idling orifice passage 84, so that it can be suitably employed as a wall spring tuning means of the equilibrium chamber 70. That is, in the present embodiment, when tuning the wall spring rigidity of the equilibrium chamber 70 including the composite spring of the elastic rubber film 62 and the diaphragm 64, the spring rigidity of the elastic rubber film 62 is larger than the spring rigidity of the diaphragm 64. It has been enlarged. As a result, the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 is increased at the time of input of engine shake or medium frequency large amplitude vibration as illustrated, and the high damping effect by the shake and medium frequency orifice passages 78 and 86 is effectively exhibited. In addition, the pressure difference between the pressure receiving chamber 68 and the equilibrium chamber 70 can be reduced when the idling basic vibration is input, and the vibration isolation effect based on the low dynamic spring characteristic by the idling orifice passage 84 can be effectively exhibited.

  Further, since the elastic rubber film 62 used as a wall spring tuning means of the equilibrium chamber 70 together with the diaphragm 64 is provided at the opening of the equilibrium chamber 70 of the idling orifice passage 84, the wall spring tuning of the equilibrium chamber 70 is performed. For example, compared with the case where the elastic rubber film is provided separately from the equilibrium chamber side opening of the idling orifice passage to the pressure receiving chamber side, the portion extending from the equilibrium chamber side opening to the elastic rubber film in the idling orifice passage Therefore, it is not necessary to strictly consider the influence on the wall spring stiffness due to the opening in the equilibrium chamber. As a result, the tuning change of the wall spring rigidity of the equilibrium chamber 70 can be facilitated, and the tuning performance of the orifice passages 78, 84, 86 for shaking, idling and idling can be improved.

  Incidentally, a specific example of the anti-vibration characteristic in the automobile engine mount 10 having the structure according to the present embodiment will be shown below. In such a specific example, a static load corresponding to the shared support load of the power unit is applied to the automobile engine mount 10 on the central axis between the first mounting bracket 12 and the second mounting bracket 14. The anti-vibration characteristics when vibration is input between the first mounting bracket 12 and the second mounting bracket 14 are shown.

  In one specific example of such vibration isolation characteristics, the shake orifice passage 78 is tuned to low frequency large amplitude vibration (frequency: about f1 = 10 Hz, amplitude: ± 1.0 mm) corresponding to engine shake. Further, in the idling orifice passage 84, deformation and displacement of the elastic rubber plate 60 and elastic rubber when high-frequency small-amplitude vibration (frequency: about f2 = 20 to 30 Hz, amplitude: ± 0.1 mm) corresponding to idling basic vibration is input. The elastic rubber plate 60 is used to exhibit a vibration isolation effect (vibration insulation effect due to the low dynamic spring) based on the resonance action of the fluid due to the deformation of the film 62 and to low frequency large amplitude vibration corresponding to an engine shake. Based on the fact that the flow restriction for idling and medium frequency orifice passages 84 and 86 due to the restraining displacement of the medium is functioning, tuning was performed so as not to be exhibited. By performing such tuning, as shown in FIG. 3, the damping coefficient C1 as an anti-vibration characteristic is shown in FIG. The high damping effect by 78 can be exhibited and an excellent anti-vibration effect can be realized. On the other hand, as shown in FIG. 4, the absolute spring constant: K1 as an anti-vibration characteristic, the deformation displacement of the elastic rubber plate 60 and the elastic rubber film against high-frequency small-amplitude vibration corresponding to the idling basic vibration. Based on the resonance action of the fluid due to the deformation of 62, the excellent vibration isolation effect (vibration insulation effect) by the low dynamic spring can be exhibited. Further, in the medium frequency orifice passage 86, medium frequency large amplitude vibration (frequency: f3 = about 11 to 15 Hz, amplitude corresponding to large amplitude vibration that is irregularly generated on the low frequency side from the idling basic vibration in the idling state. : Low frequency large amplitude corresponding to the engine shake so that the vibration isolation effect (high damping effect) based on the resonance action of the fluid due to the deformation displacement of the elastic rubber plate 60 is exerted at the time of input of about ± 0.5 mm) The vibration was tuned so as not to be exerted on the basis of the function of the idling due to the restrained displacement of the elastic rubber plate 60 and the flow restriction of the medium frequency orifice passages 84 and 86. As a result of such tuning, the damping coefficient C2 as an anti-vibration characteristic is irregularly generated on the lower frequency side than the idling basic vibration in the idling state as shown in FIG. For medium-frequency large-amplitude vibration corresponding to amplitude vibration, a high damping effect is exhibited based on the resonance action of the medium-frequency orifice passage 86 due to deformation displacement of the elastic rubber plate 60, and an excellent vibration-proofing effect can be realized. . Incidentally, an absolute spring constant as an anti-vibration characteristic for an automobile engine mount having a conventional structure made of a single rubber without enclosing an incompressible fluid is also shown in FIG. 4 as a comparative example.

  The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific descriptions in the embodiments, and various changes, modifications, and improvements based on the knowledge of those skilled in the art. Needless to say, any of these embodiments can be included in the scope of the present invention without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the balance between the idling orifice passage 84 and the idling orifice passage 84 and the flow limiting member of the idling and medium frequency orifice passages 84 and 86 including the elastic rubber plate 60, the first and second lid members 36 and 38, and the like. The elastic rubber film 62 provided at the opening of the chamber 70 is positioned to face the axial direction substantially on the center axis of the mount in the central portion of the partition member 32. It may be provided at a position that does not oppose in the direction, or at least one of the flow restricting member and the elastic rubber film may be provided at a position deviated from the mount center axis.

  In the above-described embodiment, the flow restriction members for the idling and medium frequency orifice passages 84 and 86 have different pressure differences between the pressure receiving chamber 68 and the equilibrium chamber 70 during engine shake, medium frequency large amplitude vibration, and idling basic vibration. By utilizing this, the deformation displacement of the elastic rubber plate 60 has been realized by allowing and restricting the inside of the accommodation space 58. For example, instead of the movable plate type elastic rubber plate 60, an idling orifice Similar to the elastic rubber film 62 provided at the opening of the passage 84, a movable film type rubber film that is elastically deformed based on a pressure difference between the pressure receiving chamber and the equilibrium chamber is employed, and the rubber film is the first and second lids. The flow rate of the idling and medium frequency orifice passages may be limited by abutting against a member or other restraining member and limiting the amount of deformation.

  Further, as a flow restricting member for the idling and medium frequency orifice passages 84 and 86, for example, a vibration plate is provided on the output member of the driving means such as an electromagnetic actuator, and the vibration plate is used for the idling and medium frequency orifice passages. It is arranged so as to cover the pressure receiving chamber side opening, and by controlling the vibration plate according to each input of engine shake, medium frequency large amplitude vibration, and idling basic vibration, the idling and medium frequency orifice passages are controlled. A structure that realizes flow restriction can also be adopted. In particular, the flow restricting member of this structure is not dependent on the amplitude as the flow restricting member of the movable plate structure. For example, for an engine mount for automobiles that does not have a large difference in amplitude between engine shake and medium frequency large amplitude vibration. It can be suitably employed.

  Further, in the embodiment, the elastic rubber plate 60 has a disk shape with a substantially constant thickness throughout, and the first lid as a hitting portion of the elastic rubber plate 60 in the accommodation space 58. The bottom part of the member 36 and the central part of the second lid member 38 are also formed in a flat disk shape. For example, the contact surface of the elastic rubber plate with the first or second lid member and the first or second lid It is also possible to provide a protrusion, a recess, or the like on at least one of the contact surfaces of the member with the elastic rubber plate to reduce the contact sound based on the decrease in the contact area.

  Further, in the axial direction, which is the main displacement direction of the elastic rubber plate, a positioning projection is provided on either the elastic rubber plate or the first or second lid member, and a positioning hole is formed on the other to position the elastic rubber plate. Allow the elastic rubber plate to move in the axial direction with the protrusion inserted through the positioning hole, or allow the elastic protrusion protruding from the elastic rubber plate to contact the first or second lid member with pre-compression. The axial displacement of the elastic rubber plate may be allowed by the deformation displacement of the elastic protrusion. As a result, the displacement limit means for the elastic rubber plate in the direction perpendicular to the axis causes the locking mechanism in the direction perpendicular to the axis by inserting the positioning protrusion into the positioning hole, and the wall portion of the housing cavity (first Alternatively, it may be configured by a contact mechanism that contacts the second lid member) with pre-compression.

  In the above-described embodiment, the shake orifice passage 78 and the medium frequency orifice passage 86 are configured to share the second outer peripheral flow path 74, and the medium frequency orifice passage 86 and the idling orifice passage 84 are the central flow path. However, it is of course possible to form each of these passages independently.

  In addition, the shape and size of the shake orifice passage 78, the idling orifice passage 84, the medium frequency orifice passage 86, the elastic rubber film 62, the flow restricting member for the idling and medium frequency orifice passages 84, 86, the partition member 32, etc. The form of the structure, number, arrangement, etc. can be appropriately changed in design according to the required anti-vibration effect, manufacturability, etc., and is not limited to the above embodiment.

The longitudinal cross-sectional view of the engine mount for motor vehicles as one Embodiment of this invention. The model figure of the functional structure of the engine mount for the vehicles. The graph showing the anti-vibration characteristic of the low frequency range equivalent to an engine shake in the engine mount for the said cars. 6 is a graph showing a vibration proof characteristic in a medium to high frequency range corresponding to medium frequency large amplitude vibration or idling basic vibration in the engine mount for the automobile.

Explanation of symbols

10: Automotive engine mount, 12: First mounting bracket, 14: Second mounting bracket, 16: Rubber elastic body, 36: First lid member, 38: Second lid member, 46: Lower fitting Recess, 54: first through hole, 56: second through hole, 58: accommodating space, 60: elastic rubber plate, 62: elastic rubber film, 64: diaphragm, 68: pressure receiving chamber, 70: equilibrium chamber, 78 : Shake orifice passage, 84: Idle orifice passage, 86: Medium frequency orifice passage

Claims (4)

A first attachment member attached to one of the power unit of the automobile and the vehicle body and a second attachment member attached to the other of the power unit and the vehicle body are connected by a main rubber elastic body, and the wall portion is formed by the main rubber elastic body. Forming a pressure receiving chamber in which a part of the wall is formed and an equilibrium chamber in which a part of the wall portion is formed of a flexible membrane, and incompressible fluid is enclosed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chambers In a fluid-filled engine mount for automobiles provided with an orifice passage that communicates with the equilibrium chamber,
As the orifice passage, a shake orifice passage tuned to a low frequency range corresponding to an engine shake, an idling orifice passage tuned to a high frequency range corresponding to idling fundamental vibration, and a tuning frequency of the shake orifice passage An intermediate frequency orifice passage tuned to a high frequency region and a frequency region lower than the tuning frequency of the idling orifice passage is provided, and both the opening orifices of the idling orifice passage and the intermediate frequency orifice passage in the pressure receiving chamber are covered. A flow restricting member that expands and restricts the amount of fluid flow, and further expands so as to cover the opening of the idling orifice passage in the equilibrium chamber and elastically deforms the idling orifice passage and the equilibrium chamber. Fluid-filled engine mount for a motor vehicle, characterized in that a capacity septum elastic membrane.   The movable plate can be displaced based on the pressure difference between the pressure receiving chamber and the equilibrium chamber at the portion of the pressure receiving chamber that covers both openings of the idling orifice passage and the medium frequency orifice passage, and the amount of displacement is restricted. The fluid-filled engine mount for an automobile according to claim 1, wherein the flow restricting member is configured by being arranged in a state of being restricted by contact with the member.   A partition member for partitioning the pressure receiving chamber and the equilibrium chamber is provided, the shake orifice orifice passage is formed so as to extend in the circumferential direction of the outer peripheral portion of the partition member, and the flow rate restricting member is provided at a central portion of the partition member. The idling orifice passage is disposed between the flow restricting member and the partition elastic membrane in the partition member, the partition elastic membrane being disposed so as to face the pressure receiving chamber and the partition elastic membrane facing the equilibrium chamber. The intermediate frequency orifice passage is formed so as to extend around the partition elastic membrane between the flow restricting member of the partition member and the portion facing the equilibrium chamber. Fluid-filled engine mount for automobiles.   The second mounting member includes a cylindrical portion, and the first mounting member is spaced from one opening side of the cylindrical portion and elastically connected by the main rubber elastic body. The one opening of the cylindrical portion is fluid-tightly closed, and the flexible film is disposed on the other opening side of the cylindrical portion to allow the other opening of the cylindrical portion to A fluid tightly closed with a flexible membrane, the partition member is assembled inside the cylindrical portion, and a region between the main rubber elastic body and the flexible membrane inside the cylindrical portion is covered with the partition member. The fluid-filled engine mount for an automobile according to claim 3, wherein the pressure receiving chamber and the equilibrium chamber are formed on both sides of the partition member by partitioning.

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